Compilare: user.c: In function ‘main’: user.c:3:21: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] int main() { freopen("tabela.in","r",stdin),freopen("tabela.out","w",stdout),scanf("%d%d",&l,&c),l--,c--,printf("%d",l^c); } ^ user.c:3:52: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] int main() { freopen("tabela.in","r",stdin),freopen("tabela.out","w",stdout),scanf("%d%d",&l,&c),l--,c--,printf("%d",l^c); } ^ user.c:3:83: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] int main() { freopen("tabela.in","r",stdin),freopen("tabela.out","w",stdout),scanf("%d%d",&l,&c),l--,c--,printf("%d",l^c); } ^